1. Field of the Invention
In various instances where a nail has been used to hold a member in place, such as a roof shingle, it is desirable to remove that member which means that the nail(s) first has to be removed. In the case of nailed-down roof shingles on a plywood base, as the shingles deteriorate a further layer of shingle is usually nailed over the initial layer. However, the number of layers is generally limited by fire and building construction regulations and codes which necessitate removal of the layer of shingles. Other times it is required or desirable to remove a nailed-in-place member, as for example, the removal of shingles in the case of fire. The normal way of removing a shingle is to pry it up, often leaving the nail heads exposed or requiring substantial effort to remove them completely or to hammer each nail so that the head is flush with the surface.
2. Description of the Prior Art
The Morris U.S. Pat. No. 1,428,247 discloses a nail having circumferential grooves for retaining a cement coating to aid in holding the nail in place. Boettcher's U.S. Pat. No. 2,874,603 illustrates a double-headed nail having a narrow tapered portion with webs to facilitate breaking off the extension from the normal nail.